The present invention relates to the field of photography, and more particularly to a belt drive rack and tank photographic or photosensitive material processing apparatus.
The processing of photosensitive or photographic material or film involves a series of steps such as developing, bleaching, fixing, washing and drying. These steps lend themselves to mechanization by conveying a continuous web of film or cut sheets of film or photographic paper sequentially through a series of stations or tanks, each one containing a different processing solution or liquid appropriate to the process step at that station.
There are various sizes of photographic material or film processing apparatuses, i.e., large photofinishing apparatuses and microlabs. A large photofinishing apparatus utilizes tanks that contain approximately 100 liters of each processing solution. A small photofinishing apparatus or microlab utilizes tanks that might contain less than 10 liters of processing solution.
U.S. Pat. No. 5,432,581 discribes a rack and tank arrangement that forms part of a low volume photographic material processing apparatus. The arrangement of U.S. Pat. No. 5,432,581 includes an inner rack section and an outer tank section that are easily separated. The rack and tank of U.S. Pat. No. 5,432,581 are relatively dimensioned so as to define a channel for holding a small volume of processing solution and permitting a passage of photosensitive material therethrough. In the apparatus of U.S. Pat. No. 5,432,581, a pair of input rollers are placed at an input end of the apparatus to introduce processing material into the apparatus, and a pair of output rollers are placed at an output end of the apparatus to discharge the processed photosensitive material from the apparatus. Furthermore, in addition to the input and output pair of rollers, at least three drive rollers are positioned along the processing channel, and gears are attached to designated drive rollers to drive photosensitive material along the channel. The increased use of drive rollers and gears as shown in, for example U.S. Pat. No. 5,432,581, adds cost and complexity to the apparatus. Also, the increased numbers of rollers and gears adversely affects the reliability of the apparatus since it increases the number of parts that are needed to be repaired. Furthermore, in order to properly convey cut sheets, the drive rollers need to be appropriately spaced which again, tends to increase the amount of drive rollers needed.
The present invention provides for a belt drive rack and tank processing apparatus for processing photographic material which minimizes the amount of rollers and gears necessary for the conveyance of photosensitive material. The belt drive rack and tank apparatus of the present invention requires less parts than a conventional rack and tank arrangement and facilitates the conveyance of cut sheets.
The present invention relates to an apparatus for processing photosensitive material. The apparatus comprises a tank and a rack that is adapted to be placed in the tank. The rack and the tank are relatively dimensioned so as to provide a relatively small narrow processing channel therebetween for holding a processing solution and permitting a photosensitive material to pass therethrough. The apparatus further includes a belt that extends along at least a portion of the processing channel. The belt has an outer surface which faces a photosensitive material in the processing channel and the belt is further adapted to be driven so as to convey photosensitive material along the processing channel.
The present invention further relates to a method of processing photosensitive material. The method comprises the step of introducing a photosensitive material to be processed into a relatively thin processing channel that is defined between a tank and a rack placed in the tank. The rack has a belt that extends along at least a portion of the processing channel. The method further comprises the step of conveying the photosensitive material to be processed through the processing channel by driving the belt.